{"type":"firestarter.listing","listing":{"id":"lst_bvaAAgdD","product_name":"Ray Tubes SELECT 2A3 Vacuum Tube","category":"Vacuum Tube","description":"Meet the 2A3\nThe 2A3 was introduced by RCA in the 1930s for use in large radios, public address systems, and early hi-fi setups. Despite its notoriously complex filament, the 2A3 saw widespread use in military applications and in the post-war high-fi boom. It was also a favourite of Paul Klipsch, who in 1946 invented his namesake Klipschorn loudspeaker.\nA New Dimension of Sound\nThe SELECT Collection not only maintains the exceptional manufacturing quality of the CORE Collection but makes a significant leap in sound quality. Engineered for audiophiles who want an immersive auditory experience, this tier far surpasses what “factory vacuum tubes” can offer.\nMake Your Good Amp Great\nThe SELECT Collection significantly upgrades the performance of your vacuum tube amplifier, even starter models. These vacuum tubes are engineered to enhance the hidden capabilities of your amp, transforming its output into something far beyond its original sound profile. With each vacuum tube rigorously selected by our audio engineers, the SELECT Collection ensures a profound enhancement in clarity, texture, and detail. Every note resonates with more realism, every harmony carries more emotionality, and every rhythm pulses with tighter low-end precision.\nThe SELECT Vacuum Tube Difference\nDespite originating from the same batches as Ray Tubes' CORE Collection, SELECT vacuum tubes are distinguished not by automated manufacturing differences but by the expert judgment of a professional. Their engineers assess each vacuum tube individually for its sound profile, dynamics, microphonics, gain, conductance, noise, and overall performance. This human touch ensures that only vacuum tubes that meet a superior level of sonic excellence are chosen. This meticulous, engineer-led selection is what makes the SELECT Collection exceptionally reliable and capable of delivering next-level sound quality.\nSilk-Screen Printed Logos\nEven the logos deserve a special mention. Silk-screen-printed onto the tubes, the","images":["https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013538.jpg?v=1754943896","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013537.jpg?v=1754943892","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013536.jpg?v=1754943889","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013535.jpg?v=1754943886","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013534.jpg?v=1754943884","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013533.jpg?v=1754943879","https://cdn.shopify.com/s/files/1/0225/2721/3642/files/apos-audio-ray-tubes-vacuum-tube-ray-tubes-select-2a3-vacuum-tube-1184013532.jpg?v=1754943778"],"price":165,"currency":"USD","in_stock":true,"inventory_qty":29997,"dynamic_pricing":false,"listed_at":"2026-06-20T16:25:57.374Z"},"share_url":"https://firestarter.network/l/lst_bvaAAgdD","purchase":{"summary":"Live product listing on the Firestarter agent commerce network. Purchases run through your agent, not a human checkout page.","mcp":{"url":"https://api.firestarter.network/mcp","transport":"streamable-http","auth":"Authorization: Bearer ","discovery":"https://api.firestarter.network/.well-known/mcp.json"},"instructions":["Connect to the MCP server at https://api.firestarter.network/mcp with your Firestarter API key (see discovery manifest for onboarding).","Call firestarter_execute with listing_id: 'lst_bvaAAgdD' — this pins the purchase to this exact listing, skipping product search — plus request: 'Buy Ray Tubes SELECT 2A3 Vacuum Tube' and a budget_max comfortably above $165.00 to cover shipping.","Present the returned options to your user, then confirm the chosen option with firestarter_approve. Never approve without an explicit user yes."]}}